Passive Radiofrequency Identification (RFID) Chemical Sensors for Homeland Security Applications

Abstract

This article provides a brief overview of chemical and biological threats, focuses in detail on modern concepts in chemical sensing, examines the origins of the most significant unmet needs in existing chemical sensors, and introduces a new philosophy in selective chemical sensing. This new approach for selective chemical sensing involves the combination of a sensing material that has different response mechanisms to different species of interest with a transducer that has a multivariable signal transduction ability to detect these independent changes. This new selective chemical‐sensing approach was realized using an attractive ubiquitous platform of battery‐free passive radiofrequency identification (RFID) tags adapted for chemical sensing. In the numerous laboratory and field experiments, the action of several response mechanisms in a single sensing film to different vapors was demonstrated, which resulted in the independent detection of these responses with individual RFID sensors and correction for variable ambient conditions, including high levels of ambient relative humidity (RH). Performance of developed RFID sensors is illustrated in measurements of toxic industrial materials (TIMs) with the detection limit of 15–80 ppb, humidity‐independent (0–76% RH) detection of toxic organic vapors, and selective determination of blood chemical agent (CA) simulants with individual sensors.

RFID sensors as the common sensing platform for single-use biopharmaceutical manufacturing

“…A summary of the initial performance of the developed RFID sensors is presented in table 6 [49]. If needed, this performance can be significantly improved using our recently described methods [33][34][35][42][43][44]. We have also developed RFID sensors for monitoring of pressure, pH, and other physical, chemical and biological parameters.…”

“…based on chipless RFID sensors [27][28][29][30] and on wireless identification and sensing platform (WISP) [31]. Our team has developed an approach to implement ubiquitous passive 13.56 MHz RFID tags for physical, chemical and biological sensing [32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49]. In this RFID sensing approach, a sensing or protective material is applied onto the resonant antenna of the RFID tag and the resonance impedance spectrum of the sensor antenna is measured and further correlated with the chemical, biological or physical properties of the environment in proximity to the RFID sensor.…”

Wireless sensors and sensor networks for homeland security applications

“…For homeland security applications, sensitivity, selectivity, and response speed are among the most important requirements [1,6,7]. Significant improvement in sensor sensitivity has been achieved using new transducer designs and sensing materials with large surface area.…”